Tube-joint for metal tracker-bars and method of forming the same.



N0. 880,5Q8. PATENTED MAR. s, 1908.

' T. DANQUARD. TUBE JOINT FOR METAL TRACKER BARS AND METHOD OF FORMINGTHE SAME...

APPLICATION FILED JULY 2,1906.

aijf fess s s I Methods of Forming the Same, of which following is aspecification.

UNITED STATES PATENT OFFICE.

THOMAS DANQUARD, or New YORK, Y., ASSIGNOR T THE AUTOPIANO 00., OF NewYORK, N. Y., A CORPORATION or NEW YORK.

TUBE-JOINT FOR METAL TRACKER-BARS AND METHOD OF FORMING THE SAME.

citizen of the United States, residing at New York, in the county of NewYork and State of New York, have ir vented a newand useful Tube-Jointfor Metal Tracker-Bars aIllld t e In certain modern and. improvedautomatic musical instruments, it 1s-desirable to ,use a tracker-bar ofmetal with lead or other soft metal tubes to convey the wind from thetracker-bar to the action mechanism, rubber tubing bein im racticable inmany climates A difiicu lty has arisen as to the manner of connectingthe lead tubes with the little brass tubes at the lower side of thetracker-bar.

The principal object of the present invention is to provide foraccomplishing this result in such a manner that a tight and duable jointmay be obtained without any heating or soldering which would beobjectionable in this'kind of instruments. This I accomplish byexpanding the'end of the brass tube, slipping the lead tube over theexpanded portion, inserting cement and crimping the lead at a pointbetween the expan ed part of the brass tube and the end of the leadtube.

.For a further description of a particular way in which the inventioncan conveniently be carried out, reference is to be had to theaccompanying drawings in which,

Figure 1 is a transverse sectional view of the tracker-bar showing theoutside of one of the joints. Fig. 2 is a plan of the same. Fig. Ii is aside elevation. on an enlarged scale partly in section,- showing thejointin the process of construction, and Fig. 4 is a simi-' lar viewshowing the completed joint.

.11: would be a simple matter to crimp the lead tube about the brasstube but a joint formed in this manner would not be tight and therewould be no means for preventing slipping. For the purpose of insuringan ab- .so utely tight oint and preventing any slipping oi the parts,each brass tube a, which extends from the tracker-bar, is expanded atthe. end to form a bell a. This ex ansionis made sufficiently great toenable t e bell to be inserted in the end of the lead tube 7) and tomake as tight a fit therein as may be convenient, and it has points a.It will be noticed that by forming this bell a shoulder o Specificationof Letters Patent.

Application filed July 2 190 6. Serial No. 324-406- ation, whereby thatcan be performed Patented March 8, 1908.

is provided. A certain portion 'of the tube a, adjacent to. the shouldera is covered with anysuitable kind of adhesive, such .as cement or othermaterial calculated to make a tight joint or to assist in holding thetwo scribed above. When this is accomplishcd,

the arts appear as is shown in Fig. 2.

T e next step 111 the process consists in crimping the lead tube downonto the brass tube at the part on which the cement is applied; that 1s,between the shoulder a and the end of the lead tube. This crimping maybe done in any desired way and is conveniently accomplished by the use.Of an especially constructed tool somewhat in the nature of a pair ofpliers,

It is to be observed that the crim ing re sults in forming a pair ofshoulders I) and b the latter being opposite the shoulder a and both ofthese shoulders servingto hold these parts together and prevent theirbeing-displaced by any ordinaryusage.

The cement, it must be remembered, is at this time in place between thecubes and as the trim ing v operation is preferably employed w ile thecementis in a plastic state,

the'latter can harden after the crimping o eration is performed and thusadd to the e ciency of the joint. However, a very tight joint can besecured without the use of cement, although such a joint would not besufficiently tight for some pur oses.

It will be seen, of course, t iat by the provision of the shoulders oand 5 each tube is provided with means .to prevent its being withdrawnfrom the other tube; hence, a double locking is secured and the partsare necessarily securely fixed together.

When the harder metal tube is on the inside, as described, it serves asa support for the soft metal tube during the Cllnlplll" operwithout"danger of crushing the inner tube,- but the process can be carried outWith tubes of the same hardness or even with the softer tube inside. Thelatter, however, re 'uires s ecial provisions to maintain the cylinrical s ape o the inner tube, during the crimping operation. 7

While I have illustrated and described a particular form of joint whichI at present refer to employ and have set forth a preerred method offorming this joint, I 'am aware "thatifif many modifications may be madeby any person skilled in the art and therefore, I do not wish to belimited to the exact construction or sequence of steps described andillustrated, but

What I do claim and desire to secure by Letters-Patent is 1. Thecombination of a relatively hard metal tube havin an expandedbell-shaped end provided wit a shoulder with .a relatively soft metaltube of sufiicient size to ass over the bell-shaped expanded portion ofthe first mentioned tube, said soft metal tube being crimped onto thefirst mentioned tube at a point adjacent to the shoulder thereof andbetween said shoulder and the end of the outer tube so as to constitutea shoulder on the soft metal tube opposing the shoulder on the othertube and constituting the outside of said joint, said inner tubeconstitutin a solid backing for the outer tube when the atter is crimpedthereon.

2. The combination of a tube having an expanded bell-shaped portion nearone end thereof, a second tube fittin over the exanded portion of thefirst t-u e and extend.- mg beyond the inner end of said ex andedortion, a layer of adhesive material ocated in a space between the twotubes, the outside tube eing provided with a crimpe-d portion ceaseswhereby it is forced into enga ement with the outer surface of the innertu e at a point near the ex anded portion thereof.

3. A met 0d of oining a hard-metal tube -wi th a-soft metal tube whichconsists in expending the end of the inner hard metal tube tosubstantially the diameter of the inside of the soft metal tube, passingthe outer tube over the expanded portion 0 the inner tube to project adistance beyond the same, and applyin force to crimp the outer tube onthe inner tu e between the end of the outer tube and the expandedportion of the inner tube to form. an inwardly projecting shoulderadjacent to the shoulder formed by the expanded end of the inner tube.

4. A method of uniting tubes which'con- THOMAS DANQUARD: a. s.]

Witnesses:

WM. P. CoLLrNs, CHAS. L. JENKINS.

